光在单轴晶体中传播的一个结论的证明

光进入单轴晶体后,若晶体光轴位于入射面内,双折射的o、e光都在入射面内传播。这时,o光和e光的主平面重合且都入射面内。这是单轴晶体里光传播的特殊而重要的结论,本文拟对此结论分别从惠更斯原理和费马原理出发,给出两种解析证明。

If optic axis of the uniaxial cystal lies in the plane of incidence, the propagations of o ray and e ray are always in the plane of incidence. Now the principal planes of o and e rays coincide and lies in the incident plane.It is a special and important conclusion of the propagation of light in the uniaxial crystal. In the paper, two analytic methods to prove this conclusion are given respectively from Huygens principle and Fermat's principle.